Objective: To investigate the efficacy of combining fault tree analysis with the eCASH (early Comfort using Analgesia, Sedation, and delirium monitoring) concept in the management of sedation and analgesia for ICU patients. Methods: A total of 90 patients admitted to the ICU of a certain hospital between January and December 2025 who required sedation and analgesia were selected as subjects. Using a random number table, they were divided into a control group and an observation group, comprising 45 patients each. The control group received conventional sedation and analgesia nursing management, whilst the observation group was managed using fault tree theory combined with the eCASH concept. Indicators such as RASS scores for sedation levels, pain intensity (NRS and FPS-R scores), and PSQI scores for sleep quality were compared between the two groups before and after intervention. Results: Compared with pre-intervention levels, RASS, NRS, FPS-R and PSQI scores were significantly reduced in both groups; however, the observation group showed lower scores than the control group, with statistically significant differences (p < 0.05). Conclusion: The application of fault tree theory combined with the eCASH concept in the management of sedation and analgesia for ICU patients can effectively standardise the management process and improve the efficacy of sedation and analgesia, and is worthy of clinical promotion and application.